PASOK looks set for a new round of high-level infighting after former Prime Minister and current PASOK MP Costas Simitis wrote yesterday to the party’s current leader George Papandreou to complain about his stance on the European Union’s Lisbon Treaty. In a letter that Simitis made public, the ex-premier expressed surprise that Papandreou has given his backing to the idea of holding a referendum on whether Greece should sign up to the treaty, which replaces the doomed EU Constitution. Simitis said that Papandreou’s decision is not in keeping with the policy of the governments of his father, Andreas, and Simitis himself, which had always opted for the ratification of treaties to take place in Parliament. Simitis said that putting the treaty to a referendum could weaken Greece’s position in the EU. Parliament was expected to ratify the treaty late last night. The move by the former prime minister is seen as having more to do with him striking out directly at Papandreou rather than an objection to his stance on the treaty. Papandreou, who survived a leadership challenge late last year, is expected to respond in kind to Simitis and there is speculation that he could throw the deputy out of the party. PASOK is set for a turbulent ride over the next few days, as it emerged from sources yesterday that the prosecutor investigating the Siemens bribery scandal has evidence that a former Socialist minister had irregular dealings with the company. Prosecutor Panayiotis Athanassiou allegedly discovered four unpaid invoices in the ex-minister’s name during a search of the company’s offices earlier this month.